There is more than one way to become an American. The most obvious is to be born on United States soil, but there's another option that requires a little more paperwork.

Becoming a naturalized U.S. citizen does not happen overnight. For those born elsewhere, its something of a lengthy endeavor — from application processing to the citizenship interview and exam to the actual oath of allegiance ceremony, it typically takes around 18-24 months to complete, and can take longer depending on one's personal background.

In the below gallery, we're taking a look at 16 Foreign-Born Rock Stars Who Became U.S. Citizens, all of whom went through the process mentioned above. Some of them, like Alex and Eddie Van Halen, arrived in the country as small children with their families and grew up more or less as American kids. Others, like Peter Frampton or Billy Idol, moved to the U.S. a little later in life and concluded that since they'd lived there so long, they ought to have the right to vote in American elections, which citizenship affords.

"I have lived virtually as an American since 1975," Frampton, who was compelled to become a citizen after 9/11, explained to Parade in 2011. "I had a green card, and I’ve paid taxes. I was starting to become a little more politically aware, and I meant to do it earlier. But when 9/11 happened, I called my lawyer and said, 'Let’s do it. I need to vote.' I felt very patriotic that day."

16 Rockers Who Followed the American Dream and Became US Citizens

Born elsewhere, these musicians put in the work to become full American citizens for various reasons.

Gallery Credit: Allison Rapp